1. Field of the Invention
The present invention relates to an apparatus and a method for testing air bag control unit of a vehicle.
2. Description of the Related Art
Most vehicles are provided with an air bag and a control unit thereof. The air bag control unit includes an impact deformation sensor and a microcomputer (not shown). The impact deformation sensor is provided at the front, rear, left, and right sides of a vehicle, and senses a frequency signal, namely, a frequency signal of a maximum 20 kHz generated when a vehicle collides or a vehicle body is deformed. The microcomputer receives a sensing signal from the impact deformation sensor to analyze a frequency signal, identifies presence of vehicle accident, and determines whether the air bag operates or does not. A sensing performance of a frequency signal of the impact deformation sensor is very important in the air bag system. Accordingly, a sensing performance according to frequency variation is experimented and evaluated, and evaluated contents are reflected in manufacturing a good quality impact deformation sensor.
To experiment and evaluate the performance of the impact deformation sensor, the related art generates a frequency less than about 1 kHz similar to a frequency signal generated when a vehicle collides or a vehicle body is deformed using a shaker to sample an impact state of a vehicle.
Accordingly, the impact deformation sensor senses an optionally generated frequency to generate an output signal, outputs a determining signal determining presence of an operation of an air bag using the output signal, and evaluates the determining signal output from an testing unit.
FIG. 1a shows a block diagram illustrating a vehicle deformation sensing principle of an impact deformation sensor and FIG. 1b illustrates an example of the configuration of a conventional tester for testing the impact deformation sensor.
A test product 3 such as an impact deformation sensor is mounted and fixed on a test plate 4. A shaker 1 and the test plate 4 are connected by a reciprocating rod 2. The shaker 1 reciprocates the test plate 3, causing an output signal of the impact deformation sensor to be generated. The generated output signal is tested.
The conventional tester has disadvantages. As described above, a frequency signal generated in the event of vehicle collision or deformation has a bandwidth of a maximum 20 kHz. However, a frequency sampled in the tester has a band less than 1 kHz. Namely, an impact state with respect to a frequency band ranging from 1 kHz to 20 kHz cannot be sampled.
The above information disclosed in this Background section is only for enhancement of understanding of the background of the invention and therefore it may contain information that does not form the prior art that is already known in this country to a person of ordinary skill in the art.